V.—GEO LOGY. 
Art. LXXXIV.—On the Geological Structure of Banks Peninsula, being an 
Address by Prof. Jutrus von Haast, PH.D., F.R.S., President of the 
Philosophical Institute of Canterbury. 
[Read before the Philosophical Institute of Canterbury, Tth March, 1878.) 
GENTLEMEN, —Being called again by your vote to the honourable position of 
presiding at your meetings, the agreeable duty devolves upon me to address 
you to-night at the opening of the session 1878. It has been the custom of 
your newly elected President either to offer you a review of the progress of 
science in New Zealand, to treat of some special branch of scientific 
research, or to lay before you the results of his own investigations into the 
zoology, geology, or ethnology of these interesting islands. 
With your permission, I shall follow the latter course, and venture to 
offer you some remarks upon the geological features disclosed to us by the 
piercing of the Christchurch and Lyttelton Railway Tunnel, a gigantic 
work, ever creditable to the energy and forethought of the Provincial 
Government of Canterbury in those days when only a small population had 
settled here, and the work to be undertaken was looked upon by many as 
far beyond our means. I shall preface the description of the tunnel, of 
which a section on a scale of one inch to twenty feet hangs at the wall, by 
some observations on the genetic history of Banks Peninsula, and upon the 
remarkable system of dykes, by which the older caldera walls have been 
intersected. 
When standing on the Canterbury plains the most striking feature in 
the landscape is Banks Peninsula, rising so remarkably above the sea 
horizon, that its regular form at once attracts our attention. First we 
observe a series of mountains, of which the summits are all nearly of the 
same altitude, which, as it appears to us, as far as our eye can follow their 
outlines, form nearly a circle, from which a great number of ridges slope 
with a nearly uniform gradient towards south, west, and north. Above 
them, in the centre, stands conspicuously a higher truncated mountain with 
precipitous escarpments, assuming, according to the position of the traveller, 
a different aspect. The rim of the lower mountains in front rises to an 
average height of 1,600 feet, whilst the central system attains an altitude of 
8,050 feet, On reaching Banks Peninsula from the sea, we find that several 
